Flip Equivalent Binary Trees - LeetCode

Swift Solution

class Solution {
    func flipEquiv(_ root1: TreeNode?, _ root2: TreeNode?) -> Bool {
        if root1 == nil && root2 == nil {
            return true
        } else if root1 == nil || root2 == nil {
            return false
        } else if root1!.val != root2!.val {
            return false
        } else {
            return (flipEquiv(root1!.left, root2!.right) && flipEquiv(root1!.right, root2!.left)) ||
             (flipEquiv(root1!.left, root2!.left) && flipEquiv(root1!.right, root2!.right))
        }
    }
}

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